What a returning customer is worth
One extra visit per customer changes the arithmetic. This works out the difference in pounds.
Your current customers
Rough numbers are fine — the point is the difference, not the exact figure.
How many customers visit in a month?
Distinct customers, not the number of orders.
How many times does a customer visit in a month?
Average spend per visit
How many extra visits?
One extra visit from each customer changes more than you would expect.
Your profit margin
What is left after ingredients and running costs. If you are unsure, 20% is reasonable.
Everything is worked out in your own browser. No number is sent anywhere until you press the button.
Other numbers worth a look
Wasl works this out on its own — every day, for every branch
You are still typing the numbers in by hand. Inside Wasl the same figures come straight from the orders themselves: food cost, waste, drawer variance and app commissions — without anyone opening a spreadsheet.